Add interfaces to dynamically change symbol tables used by posix_spawn, execv, and execl. This is needed for testing.

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5506 42af7a65-404d-4744-a932-0658087f49c3

9 files changed, 292 insertions, 41 deletions

diff --git a/apps/examples/Make.defs b/apps/examples/Make.defs
index de2b8939f..68d4d4340 100644
--- a/apps/examples/Make.defs
+++ b/apps/examples/Make.defs
@@ -182,6 +182,10 @@ ifeq ($(CONFIG_EXAMPLES_PWM),y)
 CONFIGURED_APPS += examples/pwm
 endif
 
+ifeq ($(CONFIG_EXAMPLES_POSIXSPAWN),y)
+CONFIGURED_APPS += examples/posix_spawn
+endif
+
 ifeq ($(CONFIG_EXAMPLES_QENCODER),y)
 CONFIGURED_APPS += examples/qencoder
 endif
diff --git a/apps/examples/Makefile b/apps/examples/Makefile
index 99312af7a..a11dbf240 100644
--- a/apps/examples/Makefile
+++ b/apps/examples/Makefile
@@ -40,8 +40,8 @@
 SUBDIRS  = adc buttons can cdcacm composite cxxtest dhcpd discover elf ftpc
 SUBDIRS += ftpd hello helloxx hidkbd igmp json keypadtest lcdrw mm modbus mount
 SUBDIRS += nettest nsh null nx nxconsole nxffs nxflat nxhello nximage
-SUBDIRS += nxlines nxtext ostest  pashello pipe poll pwm qencoder relays
-SUBDIRS += rgmp romfs serloop telnetd thttpd tiff touchscreen udp uip
+SUBDIRS += nxlines nxtext ostest  pashello pipe poll pwm posix_spawn qencoder
+SUBDIRS += relays rgmp romfs serloop telnetd thttpd tiff touchscreen udp uip
 SUBDIRS += usbserial sendmail usbstorage usbterm watchdog wget wgetjson
 
 # Sub-directories that might need context setup.  Directories may need
diff --git a/apps/examples/README.txt b/apps/examples/README.txt
index 7bfba721a..5c6332ee3 100644
--- a/apps/examples/README.txt
+++ b/apps/examples/README.txt
@@ -329,10 +329,10 @@ examples/elf
   each program in the ROMFS file system is executed.  Requires CONFIG_ELF.
   Other configuration options:
 
-    CONFIG_EXAMPLES_ELF_DEVMINOR - The minor device number of the ROMFS block.
-      For example, the N in /dev/ramN. Used for registering the RAM block driver
-      that will hold the ROMFS file system containing the ELF executables to be
-      tested.  Default: 0
+    CONFIG_EXAMPLES_ELF_DEVMINOR - The minor device number of the ROMFS block
+      driver. For example, the N in /dev/ramN. Used for registering the RAM
+      block driver that will hold the ROMFS file system containing the ELF
+      executables to be tested.  Default: 0
 
     CONFIG_EXAMPLES_ELF_DEVPATH - The path to the ROMFS block driver device.  This
       must match EXAMPLES_ELF_DEVMINOR. Used for registering the RAM block driver
@@ -348,7 +348,7 @@ examples/elf
 
      Similarly for C++ flags which must be provided in CXXELFFLAGS.
 
-  2. Your top-level nuttx/Make.defs file must alos include an approproate definition,
+  2. Your top-level nuttx/Make.defs file must also include an approproate definition,
      LDELFFLAGS, to generate a relocatable ELF object.  With GNU LD, this should
      include '-r' and '-e main' (or _main on some platforms).
 
@@ -1202,6 +1202,80 @@ examples/poll
 
   CONFIGURED_APPS += uiplib
 
+examples/posix_spawn
+^^^^^^^^^^^^^^^^^^^^
+
+  This is a simple test of the posix_spawn() API. The example derives from
+  examples/elf.  As a result, these tests are built using the relocatable
+  ELF format installed in a ROMFS file system.  At run time, the test program
+  in the ROMFS file system is spawned using posix_spawn().
+
+  Requires:
+
+    CONFIG_BINFMT_DISABLE=n           - Don't disable the binary loader
+    CONFIG_ELF=y                      - Enable ELF binary loader
+    CONFIG_LIBC_EXECFUNCS=y           - Enable support for posix_spawn
+    CONFIG_EXECFUNCS_SYMTAB="exports" - The name of the symbol table
+                                        created by the test.
+    CONFIG_EXECFUNCS_NSYMBOLS=10      - Value does not matter, it will be
+                                        corrected at runtime.
+    CONFIG_POSIX_SPAWN_STACKSIZE=768  - This default setting.
+
+  Test-specific configuration options:
+
+    CONFIG_EXAMPLES_POSIXSPAWN_DEVMINOR - The minor device number of the ROMFS
+      block. driver.  For example, the N in /dev/ramN. Used for registering the
+      RAM block driver that will hold the ROMFS file system containing the ELF
+      executables to be tested.  Default: 0
+
+    CONFIG_EXAMPLES_POSIXSPAWN_DEVPATH - The path to the ROMFS block driver
+      device.  This must match EXAMPLES_POSIXSPAWN_DEVMINOR. Used for
+      registering the RAM block driver that will hold the ROMFS file system
+      containing the ELF executables to be tested.  Default: "/dev/ram0"
+
+  NOTES:
+
+  1. CFLAGS should be provided in CELFFLAGS.  RAM and FLASH memory regions
+     may require long allcs.  For ARM, this might be:
+
+       CELFFLAGS = $(CFLAGS) -mlong-calls
+
+     Similarly for C++ flags which must be provided in CXXELFFLAGS.
+
+  2. Your top-level nuttx/Make.defs file must also include an approproate
+     definition, LDELFFLAGS, to generate a relocatable ELF object.  With GNU
+     LD, this should include '-r' and '-e main' (or _main on some platforms).
+
+       LDELFFLAGS = -r -e main
+
+     If you use GCC to link, you make also need to include '-nostdlib' or 
+     '-nostartfiles' and '-nodefaultlibs'.
+
+  3. This example also requires genromfs.  genromfs can be build as part of the
+     nuttx toolchain.  Or can built from the genromfs sources that can be found
+     at misc/tools/genromfs-0.5.2.tar.gz.  In any event, the PATH variable must
+     include the path to the genromfs executable.
+
+  4. ELF size:  The ELF files in this example are, be default, quite large
+     because they include a lot of "build garbage".  You can greatly reduce the
+     size of the ELF binaries are using the 'objcopy --strip-unneeded' command to
+     remove un-necessary information from the ELF files.
+
+  5. Simulator.  You cannot use this example with the the NuttX simulator on
+     Cygwin.  That is because the Cygwin GCC does not generate ELF file but
+     rather some Windows-native binary format.
+
+     If you really want to do this, you can create a NuttX x86 buildroot toolchain
+     and use that be build the ELF executables for the ROMFS file system.
+
+  6. Linker scripts.  You might also want to use a linker scripts to combine
+     sections better.  An example linker script is at nuttx/binfmt/libelf/gnu-elf.ld.
+     That example might have to be tuned for your particular linker output to
+     position additional sections correctly.  The GNU LD LDELFFLAGS then might
+     be:
+
+       LDELFFLAGS = -r -e main -T$(TOPDIR)/binfmt/libelf/gnu-elf.ld
+
 examples/pwm
 ^^^^^^^^^^^^
 
diff --git a/nuttx/include/unistd.h b/nuttx/include/unistd.h
index d2ace79fa..c5289624b 100644
--- a/nuttx/include/unistd.h
+++ b/nuttx/include/unistd.h
@@ -165,6 +165,12 @@ EXTERN int     rmdir(FAR const char *pathname);
 #ifdef CONFIG_LIBC_EXECFUNCS
 EXTERN int     execl(FAR const char *path, ...);
 EXTERN int     execv(FAR const char *path, FAR char *const argv[]);
+
+/* Non-standard functions to manage symbol tables */
+
+struct symtab_s; /* See include/nuttx/binfmt/symtab.h */
+EXTERN void exec_getsymtab(FAR struct symtab_s **symtab, FAR int *nsymbols);
+EXTERN void exec_setsymtab(FAR const struct symtab_s *symtab, int nsymbols);
 #endif
 
 /* Other */
diff --git a/nuttx/libc/spawn/lib_ps.c b/nuttx/libc/spawn/lib_ps.c
index b0f6e1b07..7509d6737 100644
--- a/nuttx/libc/spawn/lib_ps.c
+++ b/nuttx/libc/spawn/lib_ps.c
@@ -157,11 +157,17 @@ static int ps_exec(FAR pid_t *pidp, FAR const char *path,
                    FAR char *const argv[])
 {
   struct sched_param param;
+  FAR struct symtab_s *symtab;
+  int nsymbols;
   int pid;
   int ret = OK;
 
   DEBUGASSERT(path);
 
+  /* Get the current symbol table selection */
+
+  exec_getsymtab(&symtab, &nsymbols);
+
   /* Disable pre-emption so that we can modify the task parameters after
    * we start the new task; the new task will not actually begin execution
    * until we re-enable pre-emption.
@@ -171,13 +177,11 @@ static int ps_exec(FAR pid_t *pidp, FAR const char *path,
 
   /* Start the task */
 
-  pid = exec(path, (FAR const char **)argv, &CONFIG_EXECFUNCS_SYMTAB,
-             CONFIG_EXECFUNCS_NSYMBOLS);
-
+  pid = exec(path, (FAR const char **)argv, symtab, nsymbols);
   if (pid < 0)
     {
       ret = errno;
-      sdbg("exec failed: %d\n", ret);
+      sdbg("ERROR: exec failed: %d\n", ret);
       goto errout;
     }
 
@@ -211,6 +215,9 @@ static int ps_exec(FAR pid_t *pidp, FAR const char *path,
 
           if ((attr->flags & POSIX_SPAWN_SETSCHEDULER) == 0)
             {
+              svdbg("Setting priority=%d for pid=%d\n",
+                    param.sched_priority, pid);
+
               (void)sched_setparam(pid, &param);
             }
         }
@@ -231,6 +238,9 @@ static int ps_exec(FAR pid_t *pidp, FAR const char *path,
 
       if ((attr->flags & POSIX_SPAWN_SETSCHEDULER) != 0)
         {
+          svdbg("Setting policy=%d priority=%d for pid=%d\n",
+                attr->policy, param.sched_priority, pid);
+
           (void)sched_setscheduler(pid, attr->policy, &param);
         }
     }
@@ -262,18 +272,27 @@ static inline int spawn_close(FAR struct spawn_close_file_action_s *action)
 {
   /* The return value from close() is ignored */
 
+  svdbg("Closing fd=%d\n", action->fd);
+
   (void)close(action->fd);
   return OK;
 }
 
 static inline int spawn_dup2(FAR struct spawn_dup2_file_action_s *action)
 {
+  int ret;
+
   /* Perform the dup */
 
-  int ret = dup2(action->fd1, action->fd2);
+  svdbg("Dup'ing %d->%d\n", action->fd1, action->fd2);
+
+  ret = dup2(action->fd1, action->fd2);
   if (ret < 0)
     {
-      return errno;
+      int errcode = errno;
+
+      sdbg("ERROR: dup2 failed: %d\n", errcode);
+      return errcode;
     }
 
   return OK;
@@ -286,10 +305,14 @@ static inline int spawn_open(FAR struct spawn_open_file_action_s *action)
 
   /* Open the file */
 
+  svdbg("Open'ing path=%s oflags=%04x mode=%04x\n",
+        action->path, action->oflags, action->mode);
+
   fd = open(action->path, action->oflags, action->mode);
   if (fd < 0)
     {
       ret = errno;
+      sdbg("ERROR: open failed: %d\n", ret);
     }
 
   /* Does the return file descriptor happen to match the required file
@@ -300,12 +323,16 @@ static inline int spawn_open(FAR struct spawn_open_file_action_s *action)
     {
       /* No.. dup2 to get the correct file number */
 
+      svdbg("Dup'ing %d->%d\n", fd, action->fd);
+
       ret = dup2(fd, action->fd);
       if (ret < 0)
         {
           ret = errno;
+          sdbg("ERROR: dup2 failed: %d\n", ret);
         }
 
+      svdbg("Closing fd=%d\n", fd);
       close(fd);
     }
 
@@ -379,6 +406,7 @@ static int spawn_proxy(int argc, char *argv[])
 
             case SPAWN_FILE_ACTION_NONE:
             default:
+              sdbg("ERROR: Unknown action: %d\n", entry->action);
               ret = EINVAL;
               break;
             }
@@ -517,6 +545,9 @@ int posix_spawn(FAR pid_t *pid, FAR const char *path,
 
   DEBUGASSERT(path);
 
+  svdbg("pid=%p path=%s file_actions=%p attr=%p argv=%p\n",
+        pid, path, file_actions, attr, argv);
+
   /* If there are no file actions to be performed and there is no change to
    * the signal mask, then start the new child task directly from the parent task.
    */
@@ -559,8 +590,11 @@ int posix_spawn(FAR pid_t *pid, FAR const char *path,
   ret = sched_getparam(0, &param);
   if (ret < 0)
     {
+      int errcode = errno;
+
+      sdbg("ERROR: sched_getparam failed: %d\n", errcode);
       ps_semgive(&g_ps_parmsem);
-      return errno;
+      return errcode;
     }
 
   /* Start the intermediary/proxy task at the same priority as the parent task. */
@@ -570,8 +604,11 @@ int posix_spawn(FAR pid_t *pid, FAR const char *path,
                       (const char **)NULL);
   if (proxy < 0)
     {
+      int errcode = errno;
+
+      sdbg("ERROR: Failed to start spawn_proxy: %d\n", errcode);
       ps_semgive(&g_ps_parmsem);
-      return errno;
+      return errcode;
     }
 
    /* Wait for the proxy to complete its job */
diff --git a/nuttx/libc/spawn/spawn.h b/nuttx/libc/spawn/spawn.h
index 5d0159ff2..3f4e195cc 100644
--- a/nuttx/libc/spawn/spawn.h
+++ b/nuttx/libc/spawn/spawn.h
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/spawn/spawn.h
  *
- *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
diff --git a/nuttx/libc/unistd/Make.defs b/nuttx/libc/unistd/Make.defs
index 3811673bf..ee3ac0fc9 100644
--- a/nuttx/libc/unistd/Make.defs
+++ b/nuttx/libc/unistd/Make.defs
@@ -43,7 +43,7 @@ CSRCS +=  lib_chdir.c lib_getcwd.c
 endif
 
 ifeq ($(CONFIG_LIBC_EXECFUNCS),y)
-CSRCS +=  lib_execl.c lib_execv.c
+CSRCS +=  lib_execl.c lib_execv.c lib_execsymtab.c
 endif
 endif
 
diff --git a/nuttx/libc/unistd/lib_execsymtab.c b/nuttx/libc/unistd/lib_execsymtab.c
new file mode 100644
index 000000000..e95107d15
--- /dev/null
+++ b/nuttx/libc/unistd/lib_execsymtab.c
@@ -0,0 +1,147 @@
+/****************************************************************************
+ * libc/unistd/lib_execsymtab.c
+ *
+ *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <assert.h>
+
+#include <nuttx/arch.h>
+#include <nuttx/binfmt/symtab.h>
+
+#ifdef CONFIG_LIBC_EXECFUNCS
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+/* If CONFIG_LIBC_EXECFUNCS is defined in the configuration, then the
+ * following must also be defined:
+ */
+
+/* Symbol table used by exec[l|v] */
+
+#ifndef CONFIG_EXECFUNCS_SYMTAB
+#  error "CONFIG_EXECFUNCS_SYMTAB must be defined"
+#endif
+
+/* Number of Symbols in the Table */
+
+#ifndef CONFIG_EXECFUNCS_NSYMBOLS
+#  error "CONFIG_EXECFUNCS_NSYMBOLS must be defined"
+#endif
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+extern struct symtab_s CONFIG_EXECFUNCS_SYMTAB;
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static FAR struct symtab_s *g_exec_symtab = &CONFIG_EXECFUNCS_SYMTAB;
+static int g_exec_nsymbols = CONFIG_EXECFUNCS_NSYMBOLS;
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: exec_getsymtab
+ *
+ * Description:
+ *   Get the current symbol table selection as an atomic operation.
+ *
+ * Input Parameters:
+ *   symtab - The location to store the symbol table.
+ *   nsymbols - The location to store the number of symbols in the symbol table.
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+void exec_getsymtab(FAR struct symtab_s **symtab, FAR int *nsymbols)
+{
+  irqstate_t flags;
+
+  DEBUGASSERT(symtab && nsymbols);
+
+  /* Disable interrupts very briefly so that both the symbol table and its
+   * size are returned as a single atomic operation.
+   */
+
+  flags = irqsave();
+  *symtab   = g_exec_symtab;
+  *nsymbols = g_exec_nsymbols;
+  irqrestore(flags);
+}
+
+/****************************************************************************
+ * Name: exec_setsymtab
+ *
+ * Description:
+ *   Select a new symbol table selection as an atomic operation.
+ *
+ * Input Parameters:
+ *   symtab - The new symbol table.
+ *   nsymbols - The number of symbols in the symbol table.
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+void exec_setsymtab(FAR const struct symtab_s *symtab, int nsymbols)
+{
+  irqstate_t flags;
+
+  DEBUGASSERT(symtab);
+
+  /* Disable interrupts very briefly so that both the symbol table and its
+   * size are set as a single atomic operation.
+   */
+
+  flags = irqsave();
+  g_exec_symtab = symtab;
+  g_exec_nsymbols = nsymbols;
+  irqrestore(flags);
+}
+
+#endif /* CONFIG_LIBC_EXECFUNCS */
\ No newline at end of file
diff --git a/nuttx/libc/unistd/lib_execv.c b/nuttx/libc/unistd/lib_execv.c
index 6d09bf481..e35138be5 100644
--- a/nuttx/libc/unistd/lib_execv.c
+++ b/nuttx/libc/unistd/lib_execv.c
@@ -51,27 +51,6 @@
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
-/* If CONFIG_LIBC_EXECFUNCS is defined in the configuration, then the
- * following must also be defined:
- */
-
-/* Symbol table used by exec[l|v] */
-
-#ifndef CONFIG_EXECFUNCS_SYMTAB
-#  error "CONFIG_EXECFUNCS_SYMTAB must be defined"
-#endif
-
-/* Number of Symbols in the Table */
-
-#ifndef CONFIG_EXECFUNCS_NSYMBOLS
-#  error "CONFIG_EXECFUNCS_NSYMBOLS must be defined"
-#endif
-
-/****************************************************************************
- * Public Variables
- ****************************************************************************/
-
-extern struct symtab_s CONFIG_EXECFUNCS_SYMTAB;
 
 /****************************************************************************
  * Private Variables
@@ -140,13 +119,17 @@ extern struct symtab_s CONFIG_EXECFUNCS_SYMTAB;
 
 int execv(FAR const char *path, FAR char *const argv[])
 {
+  FAR struct symtab_s *symtab;
+  int nsymbols;
   int ret;
 
-  /* Start the task */
+  /* Get the current symbol table selection */
 
-  ret = exec(path, (FAR const char **)argv,
-             &CONFIG_EXECFUNCS_SYMTAB, CONFIG_EXECFUNCS_NSYMBOLS);
+  exec_getsymtab(&symtab, &nsymbols);
+
+  /* Start the task */
 
+  ret = exec(path, (FAR const char **)argv, symtab, nsymbols);
   if (ret < 0)
     {
       sdbg("exec failed: %d\n", errno);